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EP0717720B1 - Degazage du soufre liquide - Google Patents

Degazage du soufre liquide Download PDF

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Publication number
EP0717720B1
EP0717720B1 EP94925322A EP94925322A EP0717720B1 EP 0717720 B1 EP0717720 B1 EP 0717720B1 EP 94925322 A EP94925322 A EP 94925322A EP 94925322 A EP94925322 A EP 94925322A EP 0717720 B1 EP0717720 B1 EP 0717720B1
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EP
European Patent Office
Prior art keywords
gas
sulfur
shroud
liquid sulfur
impeller
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
EP94925322A
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German (de)
English (en)
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EP0717720A1 (fr
Inventor
David Todd R. Ellenor
James W. Smith
John H. Harbinson
Sergio De Paoli
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Apollo Environmental Systems Corp
Enersul LP
Original Assignee
Apollo Environmental Systems Corp
Procor Sulphur Services Inc
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from GB939318122A external-priority patent/GB9318122D0/en
Priority claimed from GB9403709A external-priority patent/GB9403709D0/en
Application filed by Apollo Environmental Systems Corp, Procor Sulphur Services Inc filed Critical Apollo Environmental Systems Corp
Publication of EP0717720A1 publication Critical patent/EP0717720A1/fr
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Publication of EP0717720B1 publication Critical patent/EP0717720B1/fr
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    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
    • C01B17/00—Sulfur; Compounds thereof
    • C01B17/02—Preparation of sulfur; Purification
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
    • C01B17/00—Sulfur; Compounds thereof
    • C01B17/02—Preparation of sulfur; Purification
    • C01B17/04—Preparation of sulfur; Purification from gaseous sulfur compounds including gaseous sulfides
    • C01B17/0404—Preparation of sulfur; Purification from gaseous sulfur compounds including gaseous sulfides by processes comprising a dry catalytic conversion of hydrogen sulfide-containing gases, e.g. the Claus process
    • C01B17/0456—Preparation of sulfur; Purification from gaseous sulfur compounds including gaseous sulfides by processes comprising a dry catalytic conversion of hydrogen sulfide-containing gases, e.g. the Claus process the hydrogen sulfide-containing gas being a Claus process tail gas
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
    • C01B17/00—Sulfur; Compounds thereof
    • C01B17/02—Preparation of sulfur; Purification
    • C01B17/0232—Purification, e.g. degassing
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
    • C01B17/00—Sulfur; Compounds thereof
    • C01B17/02—Preparation of sulfur; Purification
    • C01B17/04—Preparation of sulfur; Purification from gaseous sulfur compounds including gaseous sulfides

Definitions

  • the present invention is directed to the removal of hydrogen sulfide and hydrogen polysulfides from liquid sulfur in rapid and efficient manner.
  • Hydrogen sulfide is a product which may be recovered during the production of natural gas, refining operations, or as a byproduct of a number of industrial operations. In many cases the hydrogen sulfide is converted to elemental sulfur by the Claus process.
  • the basic chemistry of the Claus process is as follows: H 2 S + 3/2 O 2 ⁇ SO 2 + H 2 O 2H 2 S + SO 2 ⁇ 3/8 S 8 + 2H 2 O
  • Hydrogen sulfide is, to a limited degree, soluble in liquid sulfur. This dissolved hydrogen sulfide may react with the sulfur diradical chain species to form hydrogen polysulfides, as follows: H 2 S + • S x-1 • ⁇ H 2 S x
  • Liquid sulfur produced by the Claus process may contain from 50 to 550 ppmw of hydrogen sulfide species.
  • the hydrogen sulfide and hydrogen polysulfides slowly reach an equilibrium in the liquid sulfur which is substantially influenced by temperature. Over time, the hydrogen sulfide diffuses out of the liquid sulfur, or in cases where the sulfur has been solidified, out of the solid product. Under ambient conditions, it can take weeks for the hydrogen polysulfides to decompose to sulfur and hydrogen sulfide. The release of these hydrogen sulfide emissions may create a variety of nuisance, environmental and safety concerns, if not properly controlled. Examples of such concerns are:
  • the residence time for such processes generally ranges from several hours to, in some cases, several days.
  • the inert gas may consist of steam or nitrogen, and is generally used to reduce the risk of fire or explosion.
  • prior art systems often result in residual hydrogen sulfide and hydrogen polysulfide levels of at least about 50 ppmw.
  • the prior art also comprises mechanical systems with air or gas sparging which decrease the residence time of the liquid sulfur by increasing the degree of agitation.
  • US-A-Patent No. 4,612,020 describes a system where liquid sulfur is sprayed into two or more chambers, which are joined in series, and the liberated hydrogen sulfide is scavenged from the head space by an inert gas, such as nitrogen.
  • the residence time for the liquid sulfur as noted in this patent varies from 12 to 32 hours. Such residence times require extremely large degassing vessels to be employed. This residence time can be decreased to about 7 hours by using hetrocyclic amine catalysts.
  • the present invention employs a new approach to the degassing of liquid sulfur, which in turn facilitates dramatically reduced residence times. While reference was made earlier to liquid sulfur produced by a Claus plant, the present invention may be applied to liquid sulfur produced by other processes as well.
  • the present invention provides an improved procedure for the removal of hydrogen sulfide and hydrogen polysulfides from liquid sulfur which enables the normal degassing time to be reduced from hours or days to minutes while achieving residual H 2 S and H 2 S x levels below 5 ppmw.
  • the procedure of the invention may employ the gas-liquid contactor generally described in US-A-5,174,973 for the removal of a gaseous component from a gas stream in an aqueous system using parameters developed for aqueous systems, but modified for the removal of hydrogen sulfide and hydrogen polysulfides from liquid sulfur.
  • a method of removing hydrogen sulfide and hydrogen polysulfides from liquid sulfur which comprises providing a rotary impeller comprising a plurality of blades at a submerged location in the liquid sulfur surrounded by a shroud through which are formed a plurality of openings, feeding a stripping gas for hydrogen sulfide to the submerged location while providing a Bronsted-Lowry base catalyst for the conversion of hydrogen polysulfides to hydrogen sulfide thereat, rotating the impeller about a substantially vertical axis at a speed sufficient to draw liquid sulfur into the interior of the shroud and to distribute the stripping gas as bubbles in the liquid sulfur to the interior of the shroud and to form a gas-liquid mixture of bubbles of the gas in the liquid sulfur contained within the shroud, flowing the gas-liquid mixture from within the interior of shroud through and in contact with the openings to external of the shroud, and removing the stripping gas from the liquid sulfur.
  • the present invention provides a method of removing hydrogen sulfide and hydrogen polysulfides from liquid sulfur, which comprises a plurality of steps.
  • a rotary impeller comprising a plurality of blades is provided at a submerged location in the liquid sulfur surrounded by a shroud through which are formed a plurality of openings.
  • a stripping gas for stripping hydrogen sulfide from the liquid sulfur is fed to the submerged location.
  • the impeller is rotated about a substantially vertical axis at a speed corresponding to a blade tip velocity (v i ) of at least about 150 in/sec (at least about 4 m/s), preferably at least about 350 in/sec (at least about 9 m/s), so as to draw liquid sulfur into the interior of the shroud and to generate sufficient shear forces between the impeller and the plurality of openings in the shroud to distribute the stripping gas as bubbles in the liquid sulfur to the interior of the shroud and to effect intimate contact of the stripping gas and the liquid sulfur at the submerged location so as to form a gas-liquid mixture of bubbles of the stripping gas in the liquid sulfur contained within the shroud while effecting shearing of the gas-liquid mixture within the shroud.
  • v i blade tip velocity
  • the gas-liquid mixture is flowed from within the interior of the shroud through and in contact with the openings to external of the shroud at a gas velocity index (GVI) of at least about 4 per second per opening in the shroud, preferably at least about 18 per second per opening, so as to effect further shearing of the gas-liquid mixture and further intimate contact of the stripping gas and the liquid sulfur.
  • GVI gas velocity index
  • the method is carried out:
  • the accelerated and efficient degassing process provided herein enables equipment size to be significantly decreased for a given mass throughput and avoids the necessity and expense of constructing large holding tanks or storage pits to accommodate the traditional longer degassing residence times. Since small vessels suffice to give the needed residence time, the equipment necessary for effecting the present invention may be very compact in relation to its production rate, and requires a small capital investment and possesses low operating costs.
  • the process of the invention may be used to effect hydrogen sulfide and hydrogen polysulfide degassing of individual batches of liquid sulfur in a treatment vessel, or, alternatively, to effect degassing of a continuous feed of liquid sulfur to a treatment vessel or a series of treatment vessels.
  • the removal of hydrogen sulfide from the liquid sulfur produced by the stripping gas shifts the equilibrium of the equation: H 2 S + S x-1 ⁇ H 2 S x to the left, causing decomposition of hydrogen polysulfides.
  • This reaction is catalyzed, as outlined below, by the presence of a Bronsted-Lowry base, with stronger Bronsted-Lowry bases causing a greater catalytic effect.
  • Bronsted-Lowry base may be provided by utilizing steam as the stripping gas.
  • the hydrogen sulfide and hydrogen polysulfide stripping operation is effected in the presence of a strong Bronsted-Lowry base catalyst soluble in the liquid sulfur.
  • a strong Bronsted-Lowry base catalyst soluble in the liquid sulfur.
  • Such catalyst may be provided to the interior of the shroud and impeller combination in any convenient manner.
  • the catalyst may be introduced into the liquid sulfur flowing into a treatment vessel and/or may be introduced into the vessel, so as to be transported to the submerged location by the general circulation of liquid sulfur.
  • the catalyst may be transported by any other convenient manner to the liquid sulfur at the submerged location.
  • the catalyst may be injected into the stripping gas or may be injected directly into the vortex of liquid sulfur formed inside the shroud.
  • the difference in temperature generally existing between the stripping gas and the liquid sulfur may promote stripping of hydrogen sulfide in the presence of the catalyst.
  • a temperature differential between the cooler stripping gas and liquid sulfur of at least about 20°C is maintained.
  • the stripping gas may have a temperature of at least about 20°C and preferably less than about 100°C.
  • the present invention is concerned with a procedure for removing hydrogen sulfide and hydrogen polysulfides from liquid sulfur in a rapid and efficient manner to result in low residual hydrogen sulfide and hydrogen polysulfide levels.
  • the liquid sulfur processed herein may be that produced by a Claus plant converting hydrogen sulfide recovered from oil refining or sour gas to elemental sulfur.
  • liquid sulfur containing dissolved hydrogen sulfide and hydrogen polysulfides from any other source may be treated using the procedure of the present invention.
  • the present invention provides a method of removing hydrogen sulfide and hydrogen polysulfides from liquid sulfur, comprising a plurality of steps.
  • the method of the invention is carried out at a temperature at which sulfur is in a molten state. At temperatures above about 160°C, liquid sulfur becomes more viscous.
  • the preferred temperature range for a system as described herein is about 120°C to about 160°C, more specifically, about 125°C to 155°C.
  • the proportion of hydrogen polysulfides to hydrogen sulfide also increases with increases in temperature, and, therefore, it is preferable to degas liquid sulfur within the temperature ranges noted above.
  • a rotary impeller comprising a plurality of blades is provided at a submerged location in the liquid sulfur surrounded by a shroud through which are formed a plurality of openings, within a range of impeller to shroud diameter ratios as discussed below.
  • a stripping gas for hydrogen sulfide is fed to a submerged location in the liquid sulfur within the shroud.
  • the stripping gas may comprise steam and removes from the reaction vessel hydrogen sulfide released from the liquid sulfur in the stripping operation.
  • An amine catalyst preferably is utilized in conjunction with the steam, provided in any convenient manner in the liquid sulfur within the shroud.
  • An oxidizing gas also may be employed in the stripping gas. When such oxidizing gas is used, the oxidizing gas may be oxygen or sulfur dioxide, generally transported in an inert carrier gas, such as carbon dioxide or nitrogen or in steam.
  • An amine catalyst preferably is used in conjunction with the oxidizing gas.
  • a plurality of simultaneous reactions take place in the liquid sulfur resulting in decomposition of hydrogen polysulfides to hydrogen sulfide and stripping of hydrogen sulfide or conversion of hydrogen sulfide to sulfur.
  • Some of the reactions which may take place, depending on the nature of the stripping gas employed may be designated by the following equations: H 2 S + 1 ⁇ 2O 2 ⁇ H 2 O + S H 2 S x + 1 ⁇ 2O 2 ⁇ H 2 O + S x 2H 2 S + SO 2 ⁇ 3S + 2H 2 O 2H 2 S x + SO 2 ⁇ 2H 2 O + S 2x+1 S + O 2 ⁇ SO 2
  • the stripping gas which is passed through the liquid sulfur should comprise sufficient volume so as to remove the hydrogen sulfide released from the liquid sulfur. It is possible to use Claus process tail gas as the stripping gas since this gas contains nitrogen, water, hydrogen sulfide, sulfur dioxide, carbon dioxide and other constituents. As noted below, the use of a Claus process tail gas stream may result in simultaneous sulfur degassing and Claus plant tail gas clean up.
  • the catalyst employed herein may be any of the components known to assist the decomposition of hydrogen polysulfides to hydrogen sulfide and sulfur.
  • the catalyst is a Bronsted-Lowry base having a pK b value of less than about 10, preferably less than about 6.
  • Added catalyst materials in general are Bronsted-Lowry bases soluble in liquid sulfur, so as to promote the decomposition of the hydrogen polysulfides. Such materials preferably are sufficiently volatile to permit their stripping from the degassed liquid sulfur. Specific examples of such added catalyst materials include volatile aliphatic, cyclic and heterocyclic amines sparingly soluble in the liquid sulfur, as well as ammonia.
  • Such catalysts are preferably organic amines, such as cyclohexylamine and morpholine. Only small quantities of added catalyst are needed, generally in the low parts per million range, generally about 10 ppbw to about 10 ppmw relative to the weight of sulfur, preferably about 1 to about 5 ppmw.
  • the amine catalysts used herein also catalyze conversion of hydrogen sulfide to sulfur in the presence of sulfur dioxide, so that, when a Claus plant effluent or tail gas stream is utilized as the stripping gas for removal of hydrogen sulfide from the liquid sulfur, the presence of the amine enables Claus plant tail gas clean up and liquid sulfur degassing to be effected in a single step with a single catalyst species.
  • Such degassing operation in the presence of the amine catalyst and sulfur dioxide in the Claus plant tail gas stream may result in almost complete elimination of hydrogen sulfide from the Claus plant tail gas and from liquid sulfur degassing, leaving a gaseous effluent stream free from hydrogen sulfide emissions.
  • the sulfur dioxide employed in this procedure may be provided by burning elemental sulfur or as a slip stream from the Claus plant H 2 S burner. It may be preferred to provide a stoichiometric excess of sulfur dioxide to ensure that all hydrogen sulfide, whether in the Claus plant tail gas stream or in the liquid sulfur, is converted to sulfur, to provide a effluent stream which may contain residual sulfur dioxide.
  • Some oxygen may be added to the tail gas stream to effect sulfur dioxide formation in situ in the sulfur and reaction with hydrogen sulfide and/or hydrogen polysulfides to sulfur and water.
  • a method for the processing of a hydrogen sulfide- and sulfur dioxide-containing gas stream to remove at least one of the components therefrom comprises providing a rotary impeller comprising a plurality of blades at a submerged location in the liquid sulfur surrounded by a shroud through which are formed a plurality of openings, feeding the gas stream to the submerged location, rotating the impeller about a substantially vertical axis at a speed sufficient to draw liquid sulfur into the interior of the shroud and to distribute the gas stream as bubbles in the liquid sulfur to the interior of the shroud and to form a gas-liquid mixture of bubbles of the gas stream in the liquid sulfur contained within the shroud, and flowing the gas-liquid mixture from within the interior of the shroud through and in contact with the openings to external of the shroud, thereby to effect reaction between hydrogen sulfide and sulfur dioxide to sulfur.
  • the hydrogen sulfide- and sulfur dioxide-containing gas stream preferably is a tail gas
  • Claus plants are operated to provide a small stoichiometric excess of hydrogen sulfide over sulfur dioxide, which normally would result in residual hydrogen sulfide after reaction of the sulfur dioxide and hydrogen sulfide.
  • the composition of the gas stream may be adjusted, however, as described herein, to ensure essentially complete reaction of both hydrogen sulfide and sulfur dioxide to sulfur in the liquid sulfur.
  • the Claus plant tail gas clean up procedure generally is carried out in the presence of a catalyst for the reaction of hydrogen sulfide with sulfur dioxide. Any of the Bronsted-Lowry bases mentioned herein may be employed. It may be desirable to provide a non-volatile catalyst in the sulfur.
  • the impeller generally is rotated about a substantially vertical axis at the submerged location within the liquid sulfur at a blade tip velocity (v i ) of at least about 150 in/sec (at least about 4 m/s), preferably at least about 350 in/sec (at least about 9 m/s), more preferably at least about 500 in/sec (preferably at least about 12.5 m/s), for example, up to and greater than about 700 in/sec (up to and greater than about 18 m/s), and draws liquid sulfur into the interior of the shroud effecting vigorous circulation of liquid sulfur through the impeller and shroud combination.
  • v i blade tip velocity
  • the shear forces between the impeller blades and the plurality of openings in the shroud distribute the stripping gas in the liquid sulfur as bubbles to the interior of the shroud and forms a gas-liquid mixture of bubbles of the stripping gas in liquid sulfur contained within the shroud and effects intimate contact of the stripping gas and liquid sulfur at the submerged location while effecting shearing of the gas-liquid mixture within the shroud and initiating and sustaining rapid mass transfer.
  • the gas-liquid mixture flows from within the shroud through and in contact with the openings therein to external of the shroud at a gas velocity index (GVI) generally of at least about 4 per second per opening, preferably at least about 18 per second per opening, more preferably at least about 24 per second per opening, which causes further shearing of the gas liquid mixture and further intimate contact of gaseous phase and liquid sulfur.
  • GVI gas velocity index
  • the gas velocity index (GVI) more preferably is at least about 30 per second per opening, and may range to very high values, such as up to about 500 per second per opening, and often is in excess of about 100 per second per opening.
  • ESI Effective Shear Index
  • SEI Shear Effectiveness Index
  • Patent No. 3,993,563 (Degner) and/or to those with externally-sparged gas.
  • the ESI and SEI values employed herein preferably are determined for impeller tip speed velocities of at least about 350 in/sec (at least about 9 m/s).
  • a further important operating parameter of the process is the interrelationship of the density of the liquid phase, namely the liquid sulfur, processed by the present invention and the volumetric flow rate of gas into the reactor and this parameter may be termed the Density Index (DI).
  • the DI is determined by the expression: where Q is the volumetric flow rate of the stripping gas to the impeller (m 3 /s), Q i is the self-induction flow rate of air into water (m 3 /s), ⁇ L is the density of the liquid sulfur (kg/m 3 ), ⁇ g is the density of the gas (kg/m 3 ), ⁇ H2O is the density of water (kg/m 3 ) and ⁇ air is the density of air (kg/m 3 ).
  • the method of the invention generally is carried out at a DI value from about 1 to about 8, preferably about 3.
  • GDI Gas Displacement Index
  • Figure 1 shows a novel liquid sulfur degassing device 10 operated in accordance with one preferred embodiment of the invention.
  • the device 10 includes an enclosed housing 12 illustrated to be of cylindrical shape but any convenient geometric shape may be adopted. It is preferred that the geometric shape of the housing may be such as to avoid dead zones in the liquid phase contained within the housing.
  • a liquid sulfur feed inlet pipe 14 communicates with the interior of the housing 12 through the lower wall 16 and an overflow outlet 18 for liquid sulfur allows liquid sulfur to overflow from the interior of the housing 18 following processing therein.
  • a gas inlet 20 communicates with a standpipe 22 or draft tube extending downwardly inside the housing 12 to below the level of the body of liquid sulfur 24 contained within the vessel to enable a stripping gas for hydrogen sulfide.
  • the stripping gas generally is air but a sulfur dioxide-containing gas stream may be employed. Steam may be employed in place of or in addition to air.
  • the tail gas stream from a Claus plant also may be employed as the gas feed, thereby also effecting Claus plant tail gas clean up. As mentioned earlier, Claus plant tail gas clean up also may be effected in liquid sulfur from which the stripping of hydrogen sulfide and/or polysulfide is not required, such as liquid sulfur which has been degassed according to the invention.
  • the gas stream generally is of a volume to permit purging of hydrogen sulfide released by the liquid sulfur following decomposition of hydrogen polysulfide from the vessel 10.
  • Suitable Bronsted-Lowry catalysts included those having pK b values of less than about 10 and preferably less than about 6, and may comprise amines sparingly soluble in the liquid sulfur.
  • the catalyst may be introduced to the interior of the shroud 34 by any convenient means, such as transportation in the stripping gas stream or by direct introduction to the vortex in the shroud. If desired, a catalyst which is soluble in the liquid sulfur may be contained therein.
  • the flow rate of the stripping gas stream may range upwardly from a minimum of about 50 cu.ft/min. (about 25 dm 3 /s), for example, in excess of about 3000 cu.ft/min. (about 1400 dm 3 /s), although much higher or lower flow rates may be employed.
  • the pressure drop across the unit may be quite low and may vary from about -3 to about +40 in. H 2 O (from about -75 to about +1000 mm H 2 O), preferably from about 0 to less than about 10 in. H 2 O (250 mm H 2 O). For larger units, employing a fan or a blower to assist the gas flow rate to the impeller, the pressure drop may be greater.
  • the flow rate is further defined by the DI values discussed above.
  • a drive shaft 26 extends into the vessel 10 and has an impeller 28 mounted at its lower end just below the lower extremity of the standpipe 22.
  • a drive motor (not shown) is operatively connected to the drive shaft 26 to effect rotation of the shaft 26 and hence the impeller 28.
  • the impeller 28 comprises a plurality of radially-extending blades 30.
  • the number of such blades may vary and generally at least four blades 30 are employed, as illustrated, with the blades being equi-angularly spaced apart.
  • the impeller 28 is illustrated with the blades 30 extending vertically. However, other orientations of the blades 30 are possible.
  • the standpipe 22 has a diameter dimension related to that of the impeller 28 and the ratio of the diameter of the standpipe 22 to that of the impeller 28 generally may vary from about 1:1 to about 2:1. However, the ratio may be lower, if the impeller is mounted below the standpipe.
  • the impeller 28 generally has a height which corresponds to an approximately 1:1 ratio with its diameter, but the ratio generally may vary from about 0.3:1 to about 3:1.
  • the stripping gas may be introduced below the impeller 28 and drawn into the interior of the shroud 34 by the action of the impeller 28.
  • the ratio of the cross-sectional area of the shrouded impeller 28 to the cross-sectional area of the apparatus 10 may vary widely.
  • Another function of the impeller 28 is to distribute the introduced stripping gas bubbles within the liquid sulfur in the interior of the shroud 34. This result is achieved by rotation of the impeller 28, resulting in shear of liquid sulfur and stripping gas to form bubbles of relatively wide size distribution dimensioned so that the largest are no more than about 3 ⁇ 4 inch (20 mm) in diameter.
  • a critical parameter in determining an adequate shearing to form the gas bubbles is the velocity of the outer tip of the blades 30.
  • a blade tip velocity (v i ) of at least about 150 in/sec (at least about 4 m/s) is required to achieve efficient (i.e., 99%+) and rapid (of the order of minutes residence time) removal of hydrogen sulfide from liquid sulfur and conversion of hydrogen polysulfide, preferably at least about 350 in/sec (at least about 9 m/s), more preferably at least about 500 (at least 12.5), and up to and greater than 700 in/sec (about 18 m/s).
  • the impeller 28 is surrounded by a cylindrical stationary shroud 34 having a uniform array of circular openings 36 through the wall thereof.
  • the shroud 34 generally has a diameter slightly greater than the standpipe 22.
  • the shroud 34 is right cylindrical and stationary, it is possible for the shroud 34 to possess other shapes.
  • the shroud 34 may be tapered, with the impeller 28 optionally also being tapered.
  • the shroud 34 may be rotated, if desired, usually in the opposite direction to the impeller 28.
  • the shroud 34 is shown as a separate element from the standpipe 22. However, the shroud 34 may be provided as an extension of the standpipe 22, if desired.
  • openings 36 in the shroud are illustrated as being circular, since this structure is convenient. However, it is possible for the openings to have different geometrical shapes, such as square, rectangular or hexagonal. Further, all the openings 36 need not be of the same shape or size.
  • the shroud 34 serves a multiple function in the device.
  • the shroud 34 prevents gases from by-passing the impeller 28, assists in the formation of the vortex in the liquid sulfur necessary for gas induction, assists in achieving shearing as well as providing additional shearing and confines the gas-liquid mixture and hence maintains the turbulence and agitation produced by the impeller 28.
  • the effect of the impeller-shroud combination may be enhanced by the employment of a series of elongate baffles, provided on the internal wall of the shroud 34, preferably vertically extending from the lower end to the upper end of the openings in the shroud.
  • the gas-liquid mixture flows through and in contact with the openings 36 in the shroud which results in further shearing of the gas bubbles and further intimate contact of the gaseous and liquid phases.
  • the combined action of the impeller and shroud results in a rapid mass transfer of hydrogen sulfide into the stripping gas and catalyst into the sulfur, resulting in very rapid removal of dissolved hydrogen sulfide and decomposition of hydrogen polysulfides to sulfur and hydrogen sulfide.
  • the reactions are very rapid, in contrast to the prior art liquid sulfur degassing operations.
  • the combined action of the impeller and shroud effects circulation of liquid sulfur within the housing 12 and adequate mixing of the liquid sulfur in the body of liquid sulfur external to the shroud 32 to ensure the release of the stripping gas.
  • the openings 36 are dimensioned to permit a gas flow rate therethrough corresponding to a gas velocity index of at least about 4 per second per opening in the shroud, preferably at least about 18 per second per opening and more preferably at least about 30 per second per opening.
  • the shroud 34 is spaced only a short distance from the extremity of the impeller blades 30, in order to provide and promote the above-noted functions.
  • the ratio of the diameter of the shroud 34 to that of the impeller 28 generally is about 3:1 to about 1.1:1, preferably approximately 1.5:1.
  • the relationship of the shroud and impeller diameters may be further particularized by the ESI and SEI indices discussed above.
  • the openings 36 in the shroud 34 generally are circular, although an equivalent effect can be achieved using openings of large aspect ratio, such as slits. When such circular openings are employed, the openings 36 generally are uniformly distributed over the wall of the shroud 34 and usually are of equal size.
  • the equivalent diameter of the openings 36 often is less than about one inch (25 mm) and generally should be as small as possible without plugging, preferably about 3 ⁇ 8 to about 5 ⁇ 8 inch (about 10 to about 15 mm) in diameter, in order to provide for the required gas flow therethrough.
  • the area of each such opening 36 generally is less than the area of a circular opening having an equivalent diameter of about one inch (25 mm), preferably about 3 ⁇ 8 to about 5 ⁇ 8 inch (about 10 to about 15 mm).
  • the openings have sharp corners to promote shearing of the gas bubbles passing through the openings and contacting the edges.
  • the shroud 34 is illustrated as extending downwardly for the height of the impeller 28. It is possible for the shroud 34 to extend above the height of the impeller 28 or for less than its full height, if desired.
  • the impeller 28 is located a distance corresponding to approximately half the diameter of the impeller 28 from the bottom wall of the reactor 10. It is possible for this dimension to vary from less than about 0.25:1 to about 1:1 or greater of the proportion of the diameter dimension of the impeller.
  • This spacing of the impeller 28 from the lower wall allows liquid sulfur to be drawn into the area between the impeller 28 and the shroud 34 from the body of liquid sulfur 24 in the reactor 10.
  • a draft tube may be provided extending into the body of the liquid sulfur from the lower end of the impeller 28, to guide liquid into the region of the impeller.
  • a relatively quiescent zone is provided in the body of liquid sulfur 24 where gas bubbles disengage from the sulfur and provide a gaseous phase in the head space above the liquid level of molten sulfur in the vessel 10.
  • a further shroud may be provided surrounding the shroud 34 to promote additional mixing.
  • the liquid sulfur degassing apparatus 10 provides a very compact unit which rapidly and efficiently removes hydrogen sulfide and hydrogen polysulfides from liquid sulfur, in contrast to the large size holding tanks commonly employed in the art.
  • the novel sulfur degassing procedure employed herein may be effected as a single operation, or more preferably, a plurality of individual contactors connected in series, with each contactor having a hold-up volume commensurate with the production rate of liquid sulfur, thereby providing continuous processing of the liquid sulfur.
  • the individual contactors may vary in hold-up capacity and residence time, depending on the degassing requirements of the sulfur producing plant.
  • a typical operation effected in accordance with the invention produces a high quality product with a total hydrogen sulfide content of a few ppmw or less, or such higher value as can be accepted.
  • a polishing contactor, designed to remove catalyst from the liquid sulfur can further contribute to improve product quality.
  • the gas phases may be circulated countercurrently through the contactors.
  • Any sulfur dioxide which may be formed as a result of oxidation with air in later stages of processing with low residual hydrogen sulfide levels may be reacted with hydrogen sulfide in earlier stages, converting some of the hydrogen sulfide present to elemental sulfur.
  • the processing of the liquid sulfur in the apparatus 10 produces a low volume effluent gas which is relatively high in hydrogen sulfide content, along with some volatile impurities and traces of sulfur vapor, which is vented from the head space 38 above the body of liquid sulfur 24 in the vessel 10 through a gaseous outlet 40.
  • This effluent stream may be disposed of by incineration, or may be used as feed stream to a Claus plant for the oxidation of hydrogen sulfide, or to another hydrogen sulfide control process, such as by utilizing the procedure of US-A-5,174,973, referred to previously.
  • An experimental apparatus was set up having the structure illustrated in Figure 1. Two contactors differing in size were tested. A bench scale unit having a volume of 9 litres (16 kg) was used primarily to measure the removal rates of H 2 S and H 2 S x by measuring concentrations over time. A 970 litre pilot scale unit (1.75 tonnes) was used primarily to measure reaction rates using a steady-state flow of liquid sulfur. Sulfur produced by the Claus process from two different gas plants was used as feedstock for the two units.
  • the apparatus used to generate the data in the other Figures had an impeller 12.75 in. (32.4 cm) in diameter and 13 in. (33.0 cm) in height and a shroud having an inside diameter of 23.25 in. (59.1 cm), with 1824 x 1 ⁇ 2 in. (1.27 cm) diameter openings therethrough.
  • the contactors were operated using air as the stripping gas with and without added catalyst OPTI-MEEN 2200 (Betz Chemicals, Ltd, a proprietary aqueous solution of morpholine (10 to 30%) and cyclohexylamine (40 to 70%).
  • a typical FTIR spectrum showing H 2 S and H 2 S x in liquid sulfur feed is shown in Figure 2.
  • the curves shown in Figure 3 present the H 2 S and H 2 S x concentration plotted logarithmically against time for a typical experiment conducted with the pilot reactor using air as the stripping gas in the absence of catalyst.
  • the steeply falling line at the left edge of the graph depicts the decrease in concentration of dissolved hydrogen sulfide, while the gradually sloped curve depicts the decrease in the concentration of polysulfides. Based on the slopes of these lines, the half-lives for H 2 S and H 2 S x were calculated to be 0.75 and 48 minutes respectively.
  • Figure 4 contains a semi-logarithmic plot of the gaseous hydrogen sulfide concentration in the effluent gas against time.
  • the very fast initial decrease in H 2 S concentration can be attributed to the rapid degassing of hydrogen sulfide while the slow decrease in H 2 S concentration corresponds to decomposition of H 2 S x .
  • Figure 5 shows the effect of the addition of a small amount of catalyst in a batch test, namely 4.8 ppmw of OPTI-MEEN 2200.
  • the addition of the catalyst had a remarkable effect on the rate at which hydrogen polysulfides were converted to H 2 S.
  • Sulfur containing high initial concentrations of H 2 S and H 2 S x was degassed using air as the stripping gas in the bench scale apparatus.
  • Measurement of the hydrogen polysulfide concentration commenced about 30 minutes into the run, once the concentration fell within the calibrated range ( ⁇ 195 ppmw) and at various times over the next 25 minutes to establish a reference half-life using air as the stripping gas.
  • Figure 6 contains FTIR spectra showing the history of H 2 S and H 2 S x peaks at around the time of catalyst addition in Figure 5.
  • Figure 7 shows the spectra of sulfur samples taken from the contactor prior to and 70 seconds after injecting an amount of catalyst; nominally equivalent to 1.2 ppmw, into the air intake of the large contactor.
  • polysulfides concentration decreased with a half-life of around 0.5 minutes, again indicative of the powerful influence a very small amount of catalyst has on the polysulfide decomposition rate in the process of the invention.
  • H 2 S remained observable while H 2 S x was decomposing at a rapid rate.
  • the agreement between declining concentration rates observed with the two contactors widely different in size confirmed the validity of the scale-up factors used in the design of the larger unit.
  • Figure 9 summarizes the results of the continuous flow experiments, showing the half-life of the H 2 S x decomposition reaction as a function of catalyst concentration, expressed in ppmw with respect to the sulfur.
  • the vertical lines represent the range of values for several sets of measurements taken at a particular catalyst concentration.
  • the H 2 S x concentrations in the contactor were reduced to levels below the measurement sensitivity ( ⁇ 2 ppmw) of the FTIR system. Since the final concentration was not known in these cases, quantitative rate data were not acquired, although it is noted that the half-life was below 0.5 minutes.
  • This Figure suggests that the half life of polysulfide concentration decrease varies approximately linearly with catalyst concentration in the region between 4 and 8 ppmw. The curve, however, rises very steeply as the catalyst concentration approaches zero, since the half-life measured in batch tests with no catalyst present was approximately 45 ⁇ 15 minutes.
  • the present invention provides a novel method of degassing liquid sulfur to remove hydrogen sulfide and hydrogen polysulfides therefrom by a stripping gas in the presence of a catalyst.
  • the hydrogen sulfide is rapidly and efficiently stripped and the hydrogen polysulfides are decomposed to sulfur and hydrogen sulfide, using an impeller-shroud combination, generally in conjunction with specific operating parameters.
  • the present invention further provides a novel method of effecting the Claus reaction, particularly for Claus plant tail gas clean up, by employing the impeller-shroud combination and liquid sulfur as the medium in which sulfur dioxide and hydrogen sulfide react to form sulfur.
  • Claus plant tail gas also may be used as the stripping gas for liquid sulfur containing hydrogen sulfide and hydrogen polysulfides. Modifications are possible within the scope of the claims.

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Claims (36)

  1. Procédé d'extraction d'acide sulfhydrique et de polysulfures d'hydrogène de soufre liquide, caractérisé par :
    la disposition d'une roue rotative ayant plusieurs ailettes à un emplacement immergé dans le soufre liquide et entouré par un capot dans lequel sont formées plusieurs ouvertures,
    la transmission d'un gaz d'extraction d'acide sulfhydrique de l'emplacement immergé avec disposition d'un catalyseur basique de Bronsted-Lowry pour la conversion, sur celui-ci, des polysulfures d'hydrogène en acide sulfhydrique,
    l'entraínement en rotation de la roue autour d'un axe pratiquement vertical à une vitesse suffisante pour que le soufre liquide soit aspiré à l'intérieur du capot et que le gaz d'extraction soit réparti sous forme de bulles dans le soufre liquide vers l'intérieur du capot avec formation d'un mélange gaz-liquide avec les bulles du gaz dans le soufre liquide contenu à l'intérieur du capot,
    la circulation du mélange gaz-liquide de l'intérieur du capot exclusivement par les ouvertures vers l'extérieur du capot, et
    l'élimination du gaz d'extraction du soufre liquide.
  2. Procédé de traitement d'un courant gazeux contenant de l'acide sulfhydrique et de l'anhydride sulfureux pour l'élimination de l'un au moins de ces composés du courant, caractérisé par
    la disposition d'une roue rotative ayant plusieurs ailettes à un emplacement immergé dans le soufre liquide et entouré par un capot dans lequel sont formées plusieurs ouvertures,
    la transmission du courant gazeux à l'emplacement immergé,
    l'entraínement en rotation de la roue autour d'un axe pratiquement vertical à une vitesse suffisante pour que le soufre liquide soit aspiré à l'intérieur du capot et que le gaz d'extraction soit réparti sous forme de bulles dans le soufre liquide vers l'intérieur du capot avec formation d'un mélange gaz-liquide avec les bulles du gaz dans le soufre liquide contenu à l'intérieur du capot, et
    la circulation du mélange gaz-liquide de l'intérieur du capot exclusivement par les ouvertures vers l'extérieur du capot, si bien qu'une réaction entre l'acide sulfhydrique et l'anhydride sulfureux avec formation de soufre est exécutée.
  3. Procédé d'élimination d'acide sulfhydrique et de polysulfures d'hydrogène de soufre liquide, caractérisé par :
    la disposition d'une roue rotative ayant plusieurs ailettes à un emplacement immergé dans le soufre liquide, entouré par un capot dans lequel sont formées plusieurs ouvertures,
    la transmission d'un gaz d'extraction d'anhydride sulfurique à l'emplacement immergé,
    l'entraínement en rotation de la roue autour d'un axe pratiquement vertical à une vitesse qui correspond à une vitesse du bout des ailettes (vi) d'au moins 4 m/s (150 pouces par seconde) afin que le soufre liquide soit aspiré à l'intérieur du capot et que les forces de cisaillement créées entre la roue et les ouvertures du capot soient suffisantes pour que le gaz d'extraction soit distribué sous forme de bulles dans le soufre liquide vers l'intérieur du capot et pour qu'un contact intime entre le gaz et le soufre liquide soit effectué à l'emplacement immergé, pour la formation d'un mélange gaz-liquide de bulles de gaz dans le soufre liquide contenu à l'intérieur du capot, avec application d'un gradient de vitesse au mélange gaz-liquide à l'intérieur du capot, et
    la circulation du mélange gaz-liquide depuis l'intérieur du capot exclusivement par les ouvertures vers l'extérieur du capot avec un indice de vitesse de gaz (GVI) d'au moins 4 par seconde par ouverture du capot, afin qu'un gradient de vitesse soit en outre appliqué au mélange gaz-liquide et qu'un contact intime soit assuré entre le gaz et le soufre liquide,
    l'indice de vitesse du gaz (GVI) étant déterminé par l'expression : GVI = QP4nA2 Q étant le débit volumétrique de gaz dans la roue (m3/s), n le nombre d'ouvertures du capot, A la section de l'ouverture (m2) et P la longueur du périmètre de l'ouverture (m),
    le procédé étant exécuté
    (a) à une valeur de l'indice efficace de cisaillement (ESI) comprise entre 1 et 6 000, cette valeur étant déterminée par la relation : ESI = GVIvi x (Ds - Di)2 x 100 Ds étant le diamètre interne (m) du capot et Di le diamètre externe (m) de la roue,
    (b) à une valeur de l'indice efficace de cisaillement (SEI) comprise entre 1 et 25 telle que déterminée par la relation : SEI = QπhDivi x 100 h étant la hauteur de la roue (m), et
    (c) à une valeur d'un indice de densité (DI) comprise entre 1 et 8, cette valeur étant déterminée par la relation :
    Figure 00560001
    Qi étant le débit d'aspiration propre de l'air dans l'eau (m3/s), ρL étant la masse volumique du soufre liquide (kg/m3), ρg étant la masse volumique du gaz (kg/m3), ρH2O étant la masse volumique de l'eau (kg/m3), et ρair étant la masse volumique de l'air (kg/m3).
  4. Procédé de traitement d'un courant gazeux contenant de l'acide sulfhydrique et de l'anhydride sulfureux, caractérisé par :
    la disposition d'une roue rotative ayant plusieurs ailettes à un emplacement immergé dans le soufre liquide, entouré par un capot dans lequel sont formées plusieurs ouvertures,
    la transmission du courant gazeux à l'emplacement immergé,
    l'entraínement en rotation de la roue autour d'un axe pratiquement vertical à une vitesse qui correspond à une vitesse du bout des ailettes (vi) d'au moins 4 m/s (150 pouces par seconde) afin que le soufre liquide soit aspiré à l'intérieur du capot et que les forces de cisaillement créées entre la roue et les ouvertures du capot soient suffisantes pour que le gaz d'extraction soit distribué sous forme de bulles dans le soufre liquide vers l'intérieur du capot et pour qu'un contact intime entre le gaz et le soufre liquide soit effectué à l'emplacement immergé, pour la formation d'un mélange gaz-liquide de bulles de gaz dans le soufre liquide contenu à l'intérieur du capot, avec application d'un gradient de vitesse au mélange gaz-liquide à l'intérieur du capot, et
    la circulation du mélange gaz-liquide depuis l'intérieur du capot exclusivement par les ouvertures vers l'extérieur du capot avec un indice de vitesse de gaz (GVI) d'au moins 4 par seconde par ouverture du capot, afin qu'un gradient de vitesse soit en outre appliqué au mélange gaz-liquide et qu'un contact intime soit assuré entre le gaz et le soufre liquide, telle qu'une réaction est exécutée entre l'acide sulfhydrique et l'anhydride sulfureux contenu dans le courant gazeux en présence de soufre liquide pour la formation de soufre.
    l'indice de vitesse du gaz (GVI) étant déterminé par l'expression : GVI = QP4nA2 Q étant le débit volumétrique de gaz dans la roue (m3/s) n le nombre d'ouvertures du capot, A la section de l'ouverture (m2) et P la longueur du périmètre de l'ouverture (m),
    le procédé étant exécuté
    (a) à une valeur de l'indice efficace de cisaillement (ESI) comprise entre 1 et 6 000, cette valeur étant déterminée par la relation : ESI = GVIvi x (Ds - Di)2 x 100 Ds étant le diamètre interne (m) du capot et Di le diamètre externe (m) de la roue,
    (b) à une valeur de l'indice efficace de cisaillement (SEI) comprise entre 1 et 25 telle que déterminée par la relation : SEI = QπhDivi x 100 h étant la hauteur de la roue (m), et
    (c) à une valeur d'un indice de densité (DI) comprise entre 1 et 8, cette valeur étant déterminée par la relation :
    Figure 00580001
    Qi étant le débit d'aspiration propre de l'air dans l'eau (m3/s), ρL étant la masse volumique du soufre liquide (kg/m3), ρg étant la masse volumique du gaz (kg/m3), ρH2O étant la masse volumique de l'eau (kg/m3), et ρair étant la masse volumique de l'air (kg/m3).
  5. Procédé selon la revendication 3 ou 4, dans lequel la valeur ESI est déterminée à une valeur vi d'au moins 9 m/s (350 pouces par seconde).
  6. Procédé selon la revendication 3 ou 5, dans lequel la valeur SEI est déterminée pour une valeur vi d'au moins 9 m/s (350 pouces par seconde).
  7. Procédé selon l'une quelconque des revendications 3, 5 et 6, dans lequel la valeur ESI est comprise entre 10 et 250 et le procédé est mis en oeuvre à une valeur de l'indice d'efficacité de cisaillement (SEI) comprise entre 4 et 5.
  8. Procédé selon l'une quelconque des revendications 3 à 7, dans lequel la vitesse du bout des ailettes est d'au moins 9 m/s (350 pouces par seconde).
  9. Procédé selon la revendication 8, dans lequel la vitesse au bout des ailettes est d'au moins 12,5 m/s (500 pouces par seconde).
  10. Procédé selon l'une quelconque des revendications 3 à 9, dans lequel l'indice de vitesse du gaz est d'au moins 18 par seconde et par ouverture.
  11. Procédé selon la revendication 10, dans lequel l'indice de vitesse du gaz est d'au moins 24 par seconde et par ouverture.
  12. Procédé selon la revendication 10, dans lequel l'indice de vitesse du gaz est compris entre 300 et 500 par seconde et par ouverture.
  13. Procédé selon l'une quelconque des revendications 4 à 12, qui est exécuté avec une valeur d'indice de déplacement de gaz (GDI) comprise entre -0,5 et 0,95, déterminée par la relation : GDI = 2Vi.ω - Q2Vi.ω Vi étant le volume balayé par la roue (m3), ω le rapport de rotation de la roue (rad/s) et Q le débit volumétrique de gaz dans la roue (m3/s).
  14. Procédé selon l'une quelconque des revendications 3 à 13, exécuté avec une valeur d'indice de mélange (MI) au moins égale à -5, déterminée par la relation : MI = 2Vi.ω - QVr Vi étant le volume balayé par la roue (m3), ω la vitesse de rotation (rad/s), Q le débit volumétrique de gaz vers la roue (m3/s) et Vr le volume du réacteur (m3).
  15. Procédé selon la revendication 2 ou 4, dans lequel le courant de gaz contenant l'acide sulfhydrique et l'anhydride sulfureux est un courant de gaz de queue d'une installation Claus, et dans lequel le courant de gaz de queue de l'installation Claus contient un excès stoechiométrique d'anhydride sulfureux par rapport à l'acide sulfhydrique afin qu'une conversion pratiquement complète d'acide sulfhydrique en soufre soit réalisée dans le soufre liquide, ou le courant de gaz de queue de l'installation Claus contient suffisamment d'oxygène pour qu'il donne une quantité stoechiométrique d'anhydride sulfureux ou un excès par rapport à l'acide sulfhydrique dans le soufre liquide, si bien que la totalité pratiquement de l'acide sulfhydrique et de l'anhydride sulfureux du courant de gaz de queue est retirée dans le soufre liquide.
  16. Procédé selon l'une des revendications 2, 4 et 15, dans lequel un catalyseur de conversion de l'acide sulfhydrique en soufre par réaction avec l'anhydride sulfureux est incorporé au soufre liquide à l'emplacement immergé.
  17. Procédé selon la revendication 16, dans lequel le catalyseur est un catalyseur basique de Bronsted-Lowry ayant une valeur pKb inférieure à 10.
  18. Procédé selon la revendication 1 ou 3, dans lequel le gaz d'extraction est la vapeur d'eau, un gaz oxydant ou un courant de gaz de queue d'une installation Claus.
  19. Procédé selon la revendication 18, dans lequel le gaz d'extraction est un gaz oxydant qui est l'anhydride sulfureux en quantité suffisante pour transformer la totalité pratiquement de l'acide sulfhydrique présent dans le soufre liquide et produit par décomposition de polysulfures d'hydrogène en soufre, ou qui est l'air.
  20. Procédé selon la revendication 18, dans lequel le gaz d'extraction est un courant de gaz de queue d'une installation Claus et le courant de gaz de queue de l'installation Claus contient un excès stoechiométrique d'anhydride sulfureux par rapport à l'acide sulfhydrique afin que la conversion de l'acide sulfhydrique en soufre dans le soufre liquide soit pratiquement totale, ou le courant de gaz de queue de l'installation Claus contient suffisamment d'oxygène pour donner un excès stoechiométrique d'anhydride sulfureux par rapport à l'acide sulfhydrique dans le soufre liquide.
  21. Procédé selon les revendications 3 et 20, dans lequel le soufre liquide est traité par une série de procédures telles que définies dans la revendication 3, réalisées dans des récipients raccordés en série.
  22. Procédé selon la revendication 1, dans lequel le catalyseur basique de Bronsted-Lowry a une valeur pKb inférieure à 10.
  23. Procédé selon la revendication 22, dans lequel la valeur pKb est inférieure à 6.
  24. Procédé selon la revendication 23, dans lequel le catalyseur basique de Bronsted-Lowry est l'ammoniac ou une amine.
  25. Procédé selon la revendication 24, dans lequel l'amine est la cyclohexylamine ou la morpholine.
  26. Procédé selon les revendications 1 ou 23 à 25, dans lequel le catalyseur est utilisé en quantité comprise entre 10 ppb et 10 ppm en poids par rapport au poids de soufre.
  27. Procédé selon la revendication 28, dans lequel le catalyseur est utilisé en quantité comprise entre 1 et 5 ppm en poids par rapport au poids de soufre.
  28. Procédé selon l'une quelconque des revendications 1, 2 et 17, dans lequel le catalyseur basique de Bronsted-Lowry est disposé à l'emplacement immergé par transport vers celui-ci.
  29. Procédé selon la revendication 28, dans lequel le transport est réalisé par introduction du catalyseur dans le soufre liquide qui s'écoule dans un récipient contenant celui-ci et/ou par introduction du catalyseur dans le récipient afin qu'il soit transporté vers l'emplacement immergé par la circulation du soufre liquide dans le récipient.
  30. Procédé selon la revendication 28 ou 29, dans lequel le transport est réalisé par le gaz d'extraction (revendication 1) ou le courant gazeux (revendication 2) selon le cas.
  31. Procédé selon l'une quelconque des revendications 28 à 30, dans lequel le transport est réalisé par introduction du catalyseur directement dans un tourbillon formé par rotation de la roue à l'intérieur du capot.
  32. Procédé selon l'une quelconque des revendications 17 à 31, dans lequel le catalyseur basique de Bronsted-Lowry est une amine volatile soluble dans le soufre liquide afin que l'élimination du soufre liquide soit plus facile.
  33. Procédé selon l'une quelconque des revendications 1, 3 et 18 à 31, dans lequel le gaz d'extraction a une température inférieure d'au moins 20 °C à celle du soufre liquide.
  34. Procédé selon l'une quelconque des revendications 1, 3 et 18 à 33, dans lequel le gaz d'extraction a une température inférieure à 100 °C.
  35. Procédé selon l'une quelconque des revendications 1 à 34, mis en oeuvre à une température du soufre comprise entre 120 et 160 °C.
  36. Procédé selon la revendication 35, dans lequel la température du soufre est comprise entre 125 et 155 °C.
EP94925322A 1993-09-01 1994-08-31 Degazage du soufre liquide Expired - Lifetime EP0717720B1 (fr)

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GB939318122A GB9318122D0 (en) 1993-09-01 1993-09-01 Liquid sulphur degassing (ii)
GB9318122 1993-09-01
GB9403709A GB9403709D0 (en) 1994-02-25 1994-02-25 Liquid sulphur degassing (iv)
GB9403709 1994-02-25
PCT/CA1994/000481 WO1995006616A1 (fr) 1993-09-01 1994-08-31 Degazage du soufre liquide

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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103232026A (zh) * 2013-04-25 2013-08-07 山东三维石化工程股份有限公司青岛分公司 三级液硫脱气装置及工艺
CN108367207A (zh) * 2015-10-05 2018-08-03 氟石科技公司 用于硫的脱气的系统和方法
US11713246B2 (en) 2019-03-15 2023-08-01 Fluor Technologies Corporation Liquid sulfur degassing

Families Citing this family (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
NL1001216C2 (nl) * 1995-09-15 1997-03-20 Stork Comprimo Bv Werkwijze voor het ontgassen van zwavel.
NL1003085C2 (nl) * 1995-09-15 1997-03-20 Stork Comprimo Bv Werkwijze en inrichting voor het ontgassen van zwavel.
US5632967A (en) * 1995-09-19 1997-05-27 Goar, Allison & Associates, Inc. Process for the high pressure degassing of hydrogen sulfide from liquid sulfur
AT405721B (de) * 1997-11-07 1999-11-25 Oemv Ag Vorrichtung zum abtrennen von gasen aus flüssigkeiten sowie verwendung der vorrichtung zur abtrennung von schwefelwasserstoff aus flüssigem schwefel
US6656445B2 (en) 2000-10-13 2003-12-02 Baker Hughes Incorporated Hydrogen sulfide abatement in molten sulfur
CA2554982A1 (fr) 2003-09-26 2005-04-07 Japan Tobacco Inc. Procede pour inhiber la production de lipoproteines restantes
DE102010004062A1 (de) 2010-01-05 2011-07-07 Sterzel, Hans-Josef, Dr., 67125 Modifiziertes Claus-Verfahren zur Herstellung von polysulfanreichem Schwefel
US8329072B2 (en) 2010-11-24 2012-12-11 Brimrock International Inc. Method and system for generating sulfur seeds and granules
WO2013044104A1 (fr) 2011-09-21 2013-03-28 Fluor Technologies Corporation Configurations et procédés de traitement de gaz évacués contenant du soufre
US9346677B2 (en) 2012-08-29 2016-05-24 Sandvik Process Systems Llc Sulfur degasser apparatus and method
CN110054161A (zh) * 2019-04-22 2019-07-26 中石化广州工程有限公司 一种液硫脱气工艺及脱气装置
CN111983134B (zh) * 2019-05-24 2022-08-05 中国石油天然气股份有限公司 液体硫磺中硫化氢和多硫化氢含量的测定方法
CN114486800B (zh) * 2020-10-27 2024-04-26 中国石油化工股份有限公司 一种液硫中硫化氢含量的测定方法及液硫中多硫化氢初始含量的测定方法
EP4213960A4 (fr) * 2020-11-13 2024-06-19 Enersul Inc. Unité de pompage de dégazage rotodynamique et conception de palier de rotor
US20230416087A1 (en) * 2022-06-23 2023-12-28 Fluor Technologies Corporation Reactor system and method thereof for degassing sulfur

Family Cites Families (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR1336701A (fr) * 1962-05-24 1963-09-06 Appareil pour la purification de soufre
NL173735C (nl) * 1972-05-24 1988-06-16 Shell Int Research Werkwijze voor het verwijderen van waterstofsulfide uit gesmolten zwavel.
CA1142326A (fr) * 1979-12-11 1983-03-08 Hudson's Bay Oil And Gas Company Limited Methode de separation du soufre en presence dans les gaz par recours a la haute pression
SU1104105A1 (ru) * 1982-12-30 1984-07-23 Волго-Уральский научно-исследовательский и проектный институт по добыче и переработке сероводородсодержащих газов Способ очистки жидкой серы от сероводорода
FR2601350B1 (fr) * 1986-07-10 1988-09-30 Elf Aquitaine Procede pour l'elimination rapide de l'hydrogene sulfure contenu dans le soufre liquide et systeme catalytique utilisable pour sa mise en oeuvre
EP0504203B1 (fr) * 1989-12-05 1993-11-10 The University Of Toronto Innovations Foundation Proced et appareil destine a effectuer le contact liquide-gaz
US5174973A (en) * 1989-12-05 1992-12-29 University Of Toronto Innovations Foundation Method and apparatus for effecting gas-liquid contact
DD292635A5 (de) * 1989-12-28 1991-08-08 Ingenieurbetrieb Anlagenbau Leipzig Gmbh I.G.,De Vorrichtung zur entfernung von gasresten aus fluessigschwefel

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103232026A (zh) * 2013-04-25 2013-08-07 山东三维石化工程股份有限公司青岛分公司 三级液硫脱气装置及工艺
CN108367207A (zh) * 2015-10-05 2018-08-03 氟石科技公司 用于硫的脱气的系统和方法
EP3359271A4 (fr) * 2015-10-05 2019-04-24 Fluor Technologies Corporation Systèmes et procédés pour le dégazage de soufre
US11034583B2 (en) 2015-10-05 2021-06-15 Fluor Technologies Corporation Systems and methods for degassing of sulfur
CN108367207B (zh) * 2015-10-05 2021-08-24 氟石科技公司 用于硫的脱气的系统和方法
US11713246B2 (en) 2019-03-15 2023-08-01 Fluor Technologies Corporation Liquid sulfur degassing

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ATE214350T1 (de) 2002-03-15
EP0717720A1 (fr) 1996-06-26
WO1995006616A1 (fr) 1995-03-09
DE69430127D1 (de) 2002-04-18
CA2170021C (fr) 2000-01-25
CA2170021A1 (fr) 1995-03-09
JPH09504502A (ja) 1997-05-06
KR960704797A (ko) 1996-10-09
AU7529094A (en) 1995-03-22

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